App format spec¶

Work in progress

This spec is being defined during Phase 4. The fields and structure described here are subject to change.

Overview¶

A .olab package is a single-file archive containing everything needed to install and run a portable service on MoreOS. It bundles a squashfs filesystem image, a metadata manifest, a dm-verity root hash, and a signature.

File structure¶

<name>-<version>-<arch>.olab
├── rootfs.sqsh       # squashfs filesystem image
├── metadata.json     # package metadata
├── roothash          # dm-verity root hash
└── roothash.sig      # signature over the root hash

Metadata fields¶

Field	Type	Description
`name`	string	Package name, lowercase, hyphenated
`version`	string	Semantic version (`1.0.0`)
`arch`	string	Target architecture (`arm64`, `armv7`)
`description`	string	Short human-readable description
`source_repo`	string	URL of the upstream or packaging source repository
`tags`	list	Classification tags (e.g. `audio`, `network`, `webservice`)
`exposed_ports`	list	TCP/UDP ports the service listens on
`required_data_dirs`	list	Paths under `/data/apps/<name>/` the service expects
`min_os_version`	string	Minimum MoreOS version required
`file_listing`	list	List of files in the squashfs with sha256 hashes

Details to be finalised¶

Exact signing mechanism and key distribution
Config skeleton generator interface
Portable service profile selection (webservice, audio, network)
mkosi support alongside Docker builds

See Phase 4 in the roadmap for the full goals.